Mould for casting ingots of rectangular cross section in the metal continuous casting process

ABSTRACT

A mold for casting ingots of rectangular cross section in a continuous metal casting process, which is provided with a means for controlling heat withdrawal from the surface of an ingot both in its corners and on its face thereby allowing a skin of a uniform thickness to be obtained along the entire perimeter of an ingot on its emergence from the mold, with the quality of the cast ingots being materially improved.

United States Patent Manokhin et al.

[ 1 June 27, 1972 [54] MOULD FOR CASTING INGOTS OF RECTANGULAR CROSS SECTION IN THE METAL CONTINUOUS CASTING PROCESS [72] Inventors: Anatoly Ivanovich Manokhin, ulitsa Kan- [22] Filed:

dratjuka, 10, kv. 40; Leonid Alexandrovich Sokolov, Baikalskaya ulitsa, 40/17, kv. 42, both of Moscow, U.S.S.R.

Feb. 4, 1969 21 App1.No.: 796,329

[52] U.S.Cl ..164/283, 164/338, 164/125 [51] Int. Cl. ..B22d 11/12, B22d 27/04 [58] Field ofSearch ..l64/82, 89,273, 283,338,

[56] References Cited UNITED STATES PATENTS 3,066,364 Baier 164/82 2,242,350 Eldred ..164/89 3,085,303 Steigerwald .....164/82 3,326,270 Collins et al 164/89 3,346,037 10/1967 Bungeroth 3,437,128 4/1969 Poppmeier..... 3,450,188 6/1969 Vallak et al.... 3,463,220 8/ 1969 Moritz 3,515,202 6/1970 Bick et al... 164/89 3,520,352 7/1970 Hess ..l64/l23 X FOREIGN PATENTS OR APPLICATIONS 1,138,627 6/1957 France 1 64/283 185,516 5/1969 Germany ....l64/283 395,167 7/1933 Great Britain ..249/174 Primary Examiner-J. Spencer Overholser Assistant Examiner.lohn E. Roethel Attorney-Holman & Stern [5 7] ABSTRACT A mold for casting ingots of rectangular cross section in a continuous metal casting process, which is provided with a means for controlling heat Withdrawal from the surface of an ingot both in its corners and on its face thereby allowing a skin of a uniform thickness to be obtained along the entire perimeter of an ingot on its emergence from the mold, with the quality of the cast ingots being materially improved.

3 Claims, 3 Drawing Figures MOULD FOR CASTING INGOTS OF RECTANGULAR CROSS SECTION IN THE METAL CONTINUOUS CASTING PROCESS BACKGROUND OF THE INVENTION The present invention relates to molds for making ingots of rectangular cross section in a continuous metal casting process.

It is known from the prior art that in the continuous casting of metals the thickness of an ingots shell on its emergence from a mold should be made sufficient and uniform throughout the ingots perimeter. In such a case, it is possible to avoid development of any cracks in an ingot or an eventual break-out of liquid metal poured into the mold.

However, under the action of the temperature of the liquid metal being poured into the mold, the latter is likely to undergo thermal stresses, since its walls are not at a constant contact in all the points with the surface of an ingot to be cast, which results in a non-uniform withdrawal of heat from the ingot's surface, thereby affecting the rate of crystallization of its shell.

It has been established that the rate of crystalline growth increases in the ingots corners and decreases on its faces. This fact is especially pronounced when casting ingots of rectangular cross section and that is why it is necessary to withdraw heat from the ingots faces and to decrease the heat withdrawal at the ingots corners.

Molds were proposed, in which the internal side of the walls thereof was provided with longitudinal grooves disposed below the level of the liquid metal to be poured into the mold. Superheated steam was supplied into the grooves to ensure heat withdrawal from the ingots faces in order to increase the rate of growth of the shell or skin in these areas. However, it proved to be impracticable to control the heat withdrawal from the comers of an ingot in the prior-art molds, and the ingots thus produced suffered from defects.

It is an object of the present invention to eliminate the above disadvantage by providing a mold permitting the controlling of the heat withdrawal in a uniform manner throughout the ingots perimeter with a view to obtaining the same thickness of shell or skin of an ingot on its emergence from the mold.

SUMMARY OF THE invention The invention comprehends an improved mold for making ingots of rectangular cross section in the course of the continuous casting of metal, with the internal side of the walls of the mold being provided with grooves communicating with a coolant source.

In accordance with the invention, heat-insulating partitions are provided in the corners of the mold with the same being spaced from the ingot being cast, while the grooves are disposed only in the middle portion of the wall.

It is advisable to provide heating elements on the external side of the heat-insulating partitions.

The present invention will further be made more fully apparent from a consideration of the following description of an exemplary embodiment thereof, taken in conjunction with the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in elevation of the mold according to the invention FIG. 2 is a view taken on line lI-II of FIG. 1, the view looking in the direction of the arrows; and

FIG. 3 is a view taken on line III-III of FIG. 1, the view looking in the direction of the arrows.

DETAILED DESCRIPTION OF THE INVENTION The proposed mold has internal rectangular cross section, and is formed by copper, cooled walls 1 (FIGJ), and the lower portion thereof is provided with side cut-outs 2 extending by as much as 300 to 500 mm below the level of liquid metal in the mold. Throughout their height, the cut-outs 2 are covered with heat-insulating partitions 3 (FIG. 3), and in particular metal or ceramic units spaced by a gap 4 relative to an ingot 5 to be formed, which is shown by a dotted line. Heating elements 6 sometimes may be provided on the external side of the partition 3 for controlling the evolving heat which is emitted by the partitions 3 on the corners of the ingot 5.

On the internal side of walls 1, below the level of liquid metal in the mold, there are provided longitudinal parallel grooves 7 (FIGS. 2 and 3) which are interconnected through passages 8 and an opening 9 with a source (not shown) of a coolant being superheated steam to be supplied into the grooves 7 so as to withdraw heat from the faces of the ingot 5 to be cast.

The starting portion of the grooves 7 is disposed in the part of the mold at which the skin of the ingot 5 possesses a sufficient strength, and the grooves 7 are disposed only in the middle portion of walls 1 so that between the extreme grooves and the partitions 3 there exists a flat area 10 of the wall 1. The provisions of the grooves 7 in the middle portion of the walls is required to enable steam to enter into the gap 4 provided between the partitions 3 and ingot 5, and not to interfere with the heat withdrawal in the corners of the ingot.

During the casting of the metal, it is possible to control the heat withdrawal from the surface of the ingot to be cast by varying the degree of heating of the comers of the ingot 5 and rate of the steam supply into the grooves 7, and the heat withdrawal is controlled within a range required for the formation of a skin of a uniform thickness.

The invention allows the quality of ingots made by the continuous casting of metals to be improved, which was amply confirmed by industrial experimental tests.

What we claim is:

l. A mold for forming rectangular cross-section ingots having a skin of substantially uniform thickness in a continuous metal casting process comprising walls substantially defining the rectangular cross-section of the mold, the edges of the adjacent walls being spaced from each other at the corners of the mold; heat-insulating partitions connecting the adjacent walls at the comers, said partitions being spaced from the rectangular mold cross-section to form a gap therebetween; a coolant source; and grooves communicating with said coolant source and formed in the middle portion of the molding side of each wall, both said partitions and grooves extending below the level of the liquid metal to be poured into the mold.

2. The mold as claimed in claim 1 further comprising heating elements positioned on the side of said heat-insulating partitions opposite from the rectangular mold cross-section.

' 3. The mold as claimed in claim 2 wherein the molding side of each wall has a flat area intermediate said grooves and the edges of the adjacent walls which are spaced from each other; and said coolant is superheated steam. 

1. A mold for forming rectangular cross-section ingots having a skin of substantially uniform thickness in a continuous metal casting process comprising walls substantially defining the rectangular cross-section of the mold, the edges of the adjacent walls being spaced from each other at the corners of the mold; heat-insulating partitions connecting the adjacent walls at the corners, said partitions being spaced from the rectangular mold cross-section to form a gap therebetween; a coolant source; and grooves communicating with said coolant source and formed in the middle portion of the molding side of each wall, both said partitions and grooves extending below the level of the liquid metal to be poured into the mold.
 2. The mold as claimed in claim 1 further comprising heating elements positioned on the side of said heat-insulating partitions opposite from the rectangular mold cross-section.
 3. The mold as claimed in claim 2 wherein the molding side of each wall has a flat area intermediate said grooves and the edges of the adjacent walls which are spaced from each other; and said coolant is superheaTed steam. 